88 Mr. G. C. Champion's Revision of the Mexican 



Described by Gorham from two pairs from Cordova. A 

 female from Vera Paz fomid placed under P. (Discodon) 

 hivittatus, with the prothoracic vittae more strongly sinuate, 

 seems to belong here. P. sallaei has the front of the head, 

 a spot on the vertex, the prothorax (a sharply-defined, 

 sinuous submarginal stripe on each side excepted), and the 

 femora to near the tip, pale testaceous, and the rest of the 

 body piceous. 



21. Polemius albibucca. 



Silis albibucca, Pic, Le Nat. 1910, p. 44 {^ $). 



Moderately elongate, shining, finely pubescent; nigro-piceous 

 or piceous, the head in front, the prothorax, and the femora to rear 

 the tip, testaceous or pale testaceous. Head together with the eyes 

 broader than the prothorax in cJ; eyes large in ^, smaller in $; 

 antennae long, slender, and sparsely pilose in (Jj shorter in $. Pro- 

 thorax (cj) broader than long, obliquely bicallose on the disc, and 

 with a short carina in the middle before the base, the margins 

 broadly, subangularly dilated anteriorly and parallel thence to tlie 

 acute hind angles; ($) more transverse, the margins more broadly 

 reflexed and simply trisinuate. Elytra much wider than the 

 prothorax, subparallel, moderately long, roughly sculptured and 

 obsoletely costate. Inner claw of anterior tarsi, and outer claw of 

 the other tarsi, angularly dilated at base in (^. 



Length (excl. head) 41-51, breadth 1^2 mm. {($ $.) 



Hab. Mexico {Mus. Brit. : ?), Teapa {H. H. Smith : c^$). 



Two males and three females, agreeing nearly with Pic's 

 description, except in the paler colour of the prothorax, 

 possibly due to immaturity. This species is very closely 

 related to P. (Silis) sallaei, Gorh., of which it would appear 

 at first sight to be a form with an immaculate prothorax, 

 differing from it in the broader and more prominent tooth- 

 like dilatation of the latter in the male, and in the more 

 transverse prothorax of the female. Pic says his Silis 

 albibucca is probably near S. haematodes, Gorh., the lateral 

 prothoracic prominence of which is very differently shaped 

 and placed behind, instead of at about, the middle in ,^. 

 The two examples in the British Museum were acquired in 

 1856. Discodon oppositipunctum, Gorh., is not unlike the 

 present species, but it is larger and has one of the claws 

 of each foot cleft at the tip in (^. 



